Charles W. Bacon

Charles W. Bacon was born and raised in Bradenton, FL. He earned his B.S. degree in biology and chemistry at Clark College, Atlanta, GA, in 1965 and his Ph.D. degree in botany (fungal physiology) from the University of Michigan at Ann Arbor in 1972. Between 1972 and 1973, he was a postdoctoral fellow in the Department of Biochemistry at the University of Michigan with A. Greenberg, studying nucleotide biosynthesis in fungi and bacteria. In 1973, Bacon joined the USDA, Agricultural Research Service (ARS), Athens, GA, where he presently serves as the research leader and supervisory microbiologist.

Bacon is an internationally recognized authority in the area of fungal endophytes of grasses, primarily those that belong to the tribe Balansieae (family Clavicipitaceae), and of endophytism in grasses, which now serves as a major focus of numerous research programs worldwide. For more than 26 years prior to his appointment at ARS, scientists had tried to understand why more than 35 million acres of fescue grass grazed in the U.S. midsouth, as well as in New Zealand and Australia, caused so many animal health problems—fescue foot, fescue toxicosis, and other performance problems. Following his arrival at ARS, Bacon developed a hypothesis and implemented a research program to determine the involvement of fungi in the etiology of toxic tall fescue. In 1977, he and associates were the first to document that most tall fescue was asymptomatically infected by an endophytic fungus, which he and his research group later named Neotyphodium coenophialum. After this association was established, he discovered that this fungus produced ergot alkaloids, which caused the livestock problems.

These landmark findings provided the impetus for many research groups around the globe to further delve into the many manifestations and implications of the fascinating mutualistic symbioses between Neotyphodium/Epichloe species and the cool-season grasses. His research activities have dominated most aspects of these associations, including morphology, physiology, ecology, genetic-molecular biology, and evolution of endophytic fungi, as well as pathogenic species of the Balansieae. These plant-pathological and toxicological investigations have led to the biotechnological exploitation of endophytes for improved performance of turf and pasture grasses, with considerable potential for practical developments in the future.

Bacon developed protocols that led to the identification of ergot alkaloids from tall fescue, and these protocols are still used worldwide to assess endophytic infections and the potential for animal toxicity. In addition to his major impact on the study of forage mycotoxins and diseases, Bacon’s group also elucidated major positive roles of the endophytes, including enhanced drought tolerance, increased rooting, and greater persistence. These studies provided the foundation for Bacon’s lifelong thesis that endophytic fungi are extremely important in plants. His work has also had major practical benefits, such as influencing the creation of the first patented, endophyte-enhanced (yet livestock-friendly) cultivars of turf and forage tall fescue.

Bacon’s research is generally concerned with the action and interactions of microorganisms, plants, and animals in agricultural systems. In addition to fescue toxicosis and the Balansieae, Bacon and coworkers have researched many other aspects of plant-endophytic fungi and bacteria. Among the objects of his attention is Fusarium verticillioides (synonym F. moniliforme), a fungus that infects corn plants and produces fumonisin, a mycotoxin of major concern for food safety and livestock health. Bacon extended the concept of endophytism to include the symptomless F. verticillioides–corn association and established that this fungus produces its toxins shortly after infecting the plant seedling. He recently discovered a bacterial endophyte, Bacillus mojavensis, which by competitive exclusion can protect corn from such undesirable fungal endophytes, reducing the accumulation of mycotoxins and, thus, the potential for human and livestock poisoning. This bacterium has been patented by ARS.

Bacon has a history of providing service in the area of plant pathology. His expertise with fungal endophytes has led to his participation in national and international consulting and advising teams. He has served several terms as a panelist for the CSREES Biology of Plant–Microbe Interactions Program, has been a member of the Editorial Board of the Journal of Food Protection, and has served two terms on the Editorial Board of the Journal of Applied and Environmental Microbiology. He is a former member of the International Society of Plant Pathology Committee on Fusarium taxonomy. Bacon is an organizer, past chair, and member of the APS Standing Committee on Minorities and Cultural Diversity and the APS Mycotoxin Committee. His outreach activities include mentoring students from minority universities and serving on 1890 Capacity Building grants in plant pathology and mycology. He is a founding member and first treasurer of the International Symbiosis Society. Bacon has mentored several postdoctoral scientists and, as an adjunct professor in the Department of Plant Pathology at the University of Georgia, mentored seven graduate students as their major professor and coadvised ten others.

In recognition of his achievements, Bacon was part of a team who was awarded the USDA Superior Service Award in 1984 for “creative research contributions in finding a cause of fescue grass toxicity and incorporating those findings in a new variety of fescue having great agronomic importance.” In 2000, he was awarded the Distinguished Scientist of the Year Award by ARS in recognition of his lifetime efforts and achievements in establishing endophytic microorganisms as basic and applied tools for agricultural research. A fungal grass endophyte, Epichloe baconii, was named in recognition of his many contributions to the field of fungal endophytes.